The reality TV star wore the striking frock to her party at the Roof Garden in London's trendy Kensington and looked absolutely fabulous.
Before arriving at the glamorous venue, former PA 'Slinky Binky' tweeted her excitement, saying: "With some of my bitches about to hit my bday PARTTTYTTYYY!!! Thank u for hair @nevillesalon - tan, @StTropezTan & @patricestyliest for dress.
"We are going to get DOWWWWNNNNN.WOO."
Helping her celebrate were some of her Made In Chelsea castmates, including Ollie Locke and Fran Newman-Young.
Best mate Ollie arrived carrying a bouquet of flowers for the lucky birthday girl, while Fran rocked the chic biker chick look in a black leather jacket as she arrived with a friend.
On her Twitter account earlier in the night, Fran posted: "Happy Birthday gorgeous Miss @BinkyFelstead. Counting down the hours until tonight. Can't wait to cause unspeakable amounts of trouble xxx."
Do you like Binky's electric blue dress? Tell us what you think below!